1. Field of the Invention
This invention relates to an information signal recording and/or reproducing apparatus and more particularly to an apparatus using a tape-shaped record bearing medium having a main recording area for recording an information signal and a sub-recording area for recording a control signal, which are respectively extending in the longitudinal direction of the record bearing medium.
2. Description of the Prior Art
Conventional video signal or audio signal recording and/or reproducing appatatus called video tape recorders (VTR) or audio tape recorders include apparatus of the kind performing functions of searching for the head part of a recorded signal, and a blank part having no recorded signal which are called "head finding" and "blank search" functions. However, in arranging a VTR of the helical scanning type to have these functions, it is preferable to have a control signal recording track (or a sub-recording area) provided in the longitudinal direction along the edge part thereof in addition to helical recording tracks (or main recording area), because: In carrying out the head finding or blank search function, the tape cannot be moved at a sufficient1y high speed by tracing recording tracks to reproduce the recorded signal from each of them. That method takes too much time for the search. Further, the method merely gives information about the presence or absence of a record and thus requires some additional arrangement for head finding or searching. Besides, in the event of a partial drop-out in a video signal, that method would mistake the drop-out for a blank part or a non-recorded part.
To solve these problems, a control signal is recorded in the control track. For performing both the blank search and head search operations, the control signal to be recorded in the control track must include information indicating whether a video signal has been recorded or not and information indicating the head or leading part of a video signal. To meet this requirement, it is conceivable to form the control signal by combining more than two different kinds of signals either in a frequency multiplexing manner or in a time sharing manner. However, this necessitates not only the use of a complex circuit for forming the control signal but also the use of complex circuits for extracting and changing the different kinds of information. In addition to that, the information tends to be mistaken due to the presence of a noise component. Further, in the case where no video signal is recorded, the control signal is also not recorded. Accordingly, the part of the control signal recording track corresponding to the non-recorded part of the helical recording track also becomes a non-recorded part. This non-recorded part of the control recording track then gives information indicative of non-recording of the video signal. Therefore, in the event that the control signal is left out by a drop-out in the video signal or the like, the drop-out might be mistaken for a non-recorded part.
Meanwhile, in performing the head finding or blank search function, the tape must be brought to a stop accurately at a desired position.
However, the conventional VTR is arranged to stop the travel of the tape when the tape comes to a desired stop position after the tape is allowed to travel at a high speed. However, the force of inertia of the tape resulting from the high speed travel causes the tape to actually come to a stop after passing the desired stopping position. Further, when the tape is allowed to travel in the reverse direction in performing a head finding or blank search operation, the actual tape stopping position deviates to a great extent in the reverse direction. The tape stopping position thus becomes quite unstable.
In view of the above-stated problems of the prior art, it is a principal object of the present invention to provide an information signal recording and/or reproducing apparatus which is capable of solving all the problems mentioned above.
It is another object of this invention to provide a recording and/or reproducing apparatus which is capable of detecting a non-recorded part and a joint part of a record by means of a control signal of a single kind.
To attain these objects, an information signal recording apparatus embodying this invention comprises: First recording means for recording an information signal within a main recording area provided on a tape-shaped record bearing medium in the longitudinal direction of the record bearing medium; second recording means for recording a control signal within a sub-recording area provided on the tape-shaped record bearing medium in the longitudinal direction thereof in relation to the information signal recording action of the first recording means; and prohibiting means for prohibiting the control signal from being recorded by the second recording means for a predetermined period of time.
It is a further object of this invention to provide an information signal recording and/or reproducing apparatus which, during reproduction of a control signal, never mistakes a noise or a drop-out for a non-recorded part in the event of such an occurrence.
It is a further object of this invention to provide an information signal recording and/or reproducing apparatus which is capable of accurately distinguishing in a main recording area of a record bearing medium whether it has been recorded or not and whether it is at a joint part of a record or not by reproducing a control signal of a single kind from a sub-recording area of the medium.
To attain these objects, an apparatus arranged according to this invention to perform an information signal recording and/or reproducing operation on a tape-shaped record bearing medium having a main recording area for recording an information signal and a sub-recording area for recording a control signal in a position which is related to the recorded position of the information signal in the main recording area and is not within a non-recording part of a predetermined length arranged in a specific position, both the main recording and sub-recording areas extending in the longitudinal direction of the medium, comprises: Reproducing means for reproducing the control signal from the sub-recording area; determining means for determining whether a change which occurred in the output of the reproducing means is caused by the non-recording part of the predetermined length; moving means for moving the tape-shaped record bearing medium in the longitudinal direction thereof; and control means for controlling the moving means on the basis of the output of the reproducing means and that of the determining means.
It is a further object of this invention to provide a method and an apparatus capable of accurately and stably bringing a tape-shaped record bearing medium to a stop at a desired stopping position.
It is a further object of this invention to provide a method and an apparatus capable of accurately bringing a tape-shaped record bearing medium, to a stop at a desired stopping position regardless of the travelling speed and direction of the medium before the stop.
It is a still further object of this invention to provide a method and an apparatus capable of quickly and stably bringing a tape-shaped record bearing medium to a stop at a desired stopping position even when that medium must be allowed to travel for a predetermined period of time in determining whether the position of the medium is a desired stopping position or not.
To attain these objects, an apparatus arranged according to this invention uses a tape-shaped record bearing medium having a main recording area for recording an information signal and a sub-recording area for recording a control signal in a position which is related to the recorded position of the information signal in the main recording area and is not within a non-recording part of a predetermined length arranged in a specific position, both the main recording and sub-recording areas extending in the longitudinal direction of the medium, comprises: Reproducing means for reproducing the control signal from the sub-recording area; moving means for moving the tape-shaped record bearing medium in the longitudinal direction thereof; determining means for determining, during the travel of the tape-shaped record bearing medium caused by the moving means in the first longitudinal direction thereof at a first speed, whether or not a change occurred in the output of the reproducing means is caused by the non-recording part of a predetermined length; first control means arranged to control the moving means to cause the tape-shaped record bearing medium to travel at a second speed which is lower than the first speed in a second direction which is reversed from the first direction on the basis of the output of the determining means; and second control means arranged to control the moving means to bring the tape-shaped record bearing medium to a stop when the output of detecting means which detects the output of the reproducing means changes while the moving means is under the control of the first control means.
Futhermore, under these objects, a method according to this invention for bringing to a stop a tape-shaped record bearing medium having a main recording area for recording an information signal and a sub-recording area for recording a control signal in a position which is related to the recorded position of the information signal in the main recording area and is not within a non-recording part of a predetermined length arranged in a specific position, with both the main recording and sub-recording areas extending in the longitudinal direction of the medium, comprises: A first step of causing the tape-shaped record bearing medium to travel in a first direction at a first speed and detecting a level drop point of a reproduced control signal obtained from the control signal; a second step of determining whether the level drop point detected by the first step corresponds to a desired stopping position; a third step of causing the tape-shaped record bearing medium to travel in a second direction which is reveresed from the first direction and at a second speed which is lower than the first speed when the level drop point is determined by the second step to correspond to the desired stopping point; and a fourth step of bringing the tape-shaped record bearing medium to a stop by detecting a level rise point of the reproduced control signal while the medium is travelling in the second direction and at the second speed.
The above and further objects and features of this invention will become apparent from the following detailed description of a preferred embodiment thereof taken in conjunction with the accompanying drawings.